An FPGA implementation of 200MBPS CI/OFDM modem for satellite communication systems

A prototype design of a modem for a satellite communication system is presented. We apply CI/OFDM (Carrier Interferometry - Orthogonal Frequency Division Multiplexing) to the system, which achieves high bitrate and efficient use of frequency band and reduces large peak power in conventional OFDM but requires more heavy computation. The modem consists of digital baseband processes as FEC (Forward Error Correction), QAM (Quadrature Amplitude Modulation), FFT (Fast Fourier Transform), CI (Carrier Interferometry), and so on. For the iterations of the prototyping and various experiments of the advanced communication, the prototype should be flexible and ready to accept various parameters, modes, and compositions efficiently. We design FPGA (Field Programmable Gate Array) prototypes with parameterized modules, which enable various parameters and modes, under strict and uniform modularization rules which enable easy change of the composition. Our prototype achieves the required performance 200Mbps and contributes to a demonstration of an advanced satellite communication system.